Re: unmarked linkend awareness by XML engines

At 17:01 29/12/96 -0500, Steven R. Newcomb wrote:

>Much better to provide a session-start document instead that contains
>the copyright and license information, and that links to the valuable
>asset.  The user naturally and normally starts the session by entering
>the session-start document, because that's the only way documented by
>the provider.  (Similarly, in books, one knows that the natural and
>normal procedure is to start at the upper left hand corner of page one
>and read forwards, but nothing prevents you from starting somewhere in
>the middle and reading backwards if you prefer.)  By means of a
>hyperlink, the session start document automagically traverses the user
>to the valuable read-only asset.  Upon arrival at the read-only asset,
>the BOS is still pretty much guaranteed to include the session-start
>document; otherwise, the user couldn't have arrived at the read-only

This only works if your read-only asset inherits the BOS of all the
documents in the chain used to reach it, or the BOS of a start point
document that covers the whole of a document set. What you are talking about
in the first of these is the browser's History list. But how on earth do I
know which entry in my History list is the one that contains the copyright
notice and any necessary disclaimers?

On the Web there is no guarantee that you will access a document via its
session start document. In fact, for any reasonably large data set you can
normally guarantee that you won't. So the question becomes "how do you
identify the BOS" associated with this page if it resides with the session
start document". What you need to do is to have a pointer to the BOS that
says "This Web page should be used with this BOS". (Isn't this the catalog
for the file set?)

>If the user is running an application which is like any
>typical Web browser, the session-start document is still in a local
>cache, so the frailty of the Web network is not even an issue.  The
>session-start document contains links which effectively place one or
>more hot links at various points in the read-only asset back to the
>session-start document.  When traversed, those hot links can take the
>user to the copyright notice or the license agreement, or whatever.

How? The problem is which set of links should be used. If I annotate one of
your documents the session start document will point to my copyright notice.
When looking at a hot-link I have added to your document, according to your
methods, I need to know both who created the link and, more importantly, who
created the text being referenced. This is only possible if your page
contains a pointer to your copyright information and my link contains a
pointer to my copyright notice.

>The valuable read-only asset never needs to be edited unless its
>substantive content must change.  The session-start document can be
>changed at the pleasure of the owner of the read-only asset, with no
>danger to the main asset.  In fact, it can easily be made to bear a
>license stamp unique to each licensee.

I don't see how this last would work if the locator for the copyright info
is stored as part of the read-only asset. Unique use of a license over the
web implies dynamic allocation of some information that needs to be
maintained by the browser in some safe way. This has to be done using some
form of cookie. Can cookies reroute locators?
Martin Bryan, The SGML Centre, Churchdown, Glos. GL3 2PU, UK 
Phone/Fax: +44 1452 714029   WWW home page: http://www.u-net.com/~sgml/